"Appreciate your allies... you don't have that many," Trump is warned.---------------------

President Donald Trump has left for a Nato summit in Brussels with a stark warning from European Council President Donald Tusk.

Ahead of his visit, Mr Trump hit out at the EU on trade and at his Nato allies for failing to spend enough on defence.

Accusing the president of criticising Europe "almost daily", Mr Tusk said the EU spent more than Russia on defence and as much as China.

"Dear America, appreciate your allies, after all you don't have that many." Mr Tusk also made the point that the US did not and would not have a better ally than the EU, reminding the president that it was European troops who had fought and died in Afghanistan after the 11 September 2001 attacks on the US.

Dear @realDonaldTrump. US doesn’t have and won’t have a better ally than EU. We spend on defense much more than Russia and as much as China. I hope you have no doubt this is an investment in our security, which cannot be said with confidence about Russian & Chinese spending :-)

The EU Council leader said pointedly that when Mr Trump did meet Mr Putin on 16 July "it is always worth knowing who is your strategic friend and who is your strategic problem."

Before he left Andrews Air Force Base, President Trump reiterated his demand for the US to pay less and other members of the Western military alliance to pay more, and he linked the issue to the EU's trade surplus with the US.

Getting ready to leave for Europe. First meeting - NATO. The U.S. is spending many times more than any other country in order to protect them. Not fair to the U.S. taxpayer. On top of that we lose $151 Billion on Trade with the European Union. Charge us big Tariffs (& Barriers)!

Last month, the US raised fears of a trade war by slapping tariffs on steel and aluminium from the EU, Canada, Mexico and other US allies. The EU hit back with tariffs on products including motorcycles and orange juice. According to EU statistics, the EU's trade surplus in 2017 was $140bn (€120bn; £106bn).

On Nato, President Trump's main objection is that a number of member states have not increased their defence budgets to the target of 2% of economic output.

Nato countries have agreed to raise military spending by 2024, although Germany and Spain are unlikely to meet the target.

SOURCE.------------------------Some comments and links (comments are from OP, feel free to disagree).

(OP: A large part of my comments were motivated by the fact that Trump apparently never met a nuance he didn't want to trample over.)

(1) On the supposed trade deficit with the European Union.

See the following reference: "Claim: The US is suffering from a trade imbalance, with a trade deficit of $800bn (£579bn) in 2017. Reality Check verdict: The President is incorrect about the US trade deficit - it was $566bn (£410bn) in 2017. Economists generally agree that neither trade deficits nor surpluses are necessarily 'good' or 'bad' for an economy."

From this reference: "What’s more, eliminating the trade deficit would not, on its own, make America great again, as Mr. Trump promises. In fact, trying to eliminate the trade deficit could mean giving up some of the key levers of power that allow the United States to get its way in international politics. Getting rid of the trade deficit could very well make America less great. The reasons have to do with the global reserve currency, economic diplomacy and something called the Triffin dilemma." (Source explains what Trump is not getting about trade deficits -very interesting.)

(2) Some comments on the war of words on defence spending in Nato.

What Trump's tweet neglects to mention is the measure he is using when discussing defence spending, because the picture definitely changes depending on the measure used.

*Also it is important to note that the years do vary a bit between some of the figures I have reported, however the comparison is probably still acceptable since we're discussing something which is understood to be a long standing 'problem' (by Trumpers anyways).

Forbes reported on the top countries in terms of percent of global military expenditure in 2016. This is how big each country's share of the global 'pie' or total amount spent on defence worldwide was. The country who had the biggest percentage, by far, was the US (36.0% vs 13.0% for the country in second place, which was China). The problem with this measure however, is that it does not take into account the number of people in a country (i.e. presumably a country with more people would at least have the potential to spend more) and it also does not take into account the size of a country's economy (i.e. a country with more revenue could hypothetically afford to spend more on defence). So yes the United States spent much more than Israel, for instance, but is this really a good comparison since Israel is a much smaller country in terms of population? (See here and here for actual population sizes.)

Another measure seems to be percent (%) of a country's GDP in a year. ("The gross domestic product (GDP) is one of the primary indicators used to gauge the health of a country's economy. It represents the total dollar value of all goods and services produced over a specific time period, often referred to as the size of the economy.") This measure does take into account the size of a country's economy and is therefore somewhat linked to population size just because more people can hypothetically produce more (although other factors such as productivity should be involved). An important criticism of GDP as a measure of the health of an economy, more generally, is that it DOES NOT take into account the distribution of wealth within a country (in other words whether two people have all the money and resources in the country versus 2 billion people sharing the money and resources). In terms of military expenditure this is a better measure than the % global expenditure however.In terms of % GDP it is true that Canada and the EU are spending much less than the United States on defence (1.2% for Canada, 1.5% for the Euro area, 3.1% for the United States). One thing that is interesting however (and where Trump again gets it wrong, assuming I read his tweet correctly) in terms of % of GDP is that the US IS NOT the largest spender worldwide, according to this measure (i.e. Russia is at 4.2%, Saudi Arabia at 10.2%, Lebanon at 4.7%, Oman at 12.0%, Middle East and North Africa 5.7%).

A third measure is military spending per capita. Here again the picture changes a bit. Per capita means averaged over an entire population. In other words this is a measure which adjusts for population size (i.e. basically the number of dollars spent is divided by the number of people in the country). According to this measure, which I had a lot of difficulty finding online and had to calculate myself, Saudi Arabia spends about double what the US does, per capita (i.e. per person).

So all in all yes, Europe (and Canada, from what I saw) do spend less than the US. However it is not accurate to state that the US spends more than any other nation on defence because some non Nato nations do seem to spend more. A lot more. (However it is important to note that Tusk was wrong too, according to the figures above.)

Final OP note: (This paragraph is strictly the OP's personal ideas.) It seems to me that the above discussion also fails to consider philosophical differences with regards to defence, as well. While it is somewhat hypocritical of Canada (i.e. I am Canadian, which is why I mention this specific example) to spend less (i.e. given that Canada definitely does benefit from US defense spending, which has been outlined by other US presidents), I would suggest that there may also be some fundamental differences in how different countries view the necessity of defence spending. (Although I will openly admit I have no data on this.) The 'need' for defence spending should also, IMO, be affected by the degree of belligerence of one's foreign policy.

What I think I find the most depressing is the way in which the Republicans are actively working to subvert US democracy -a democracy that wasn't all that democratic to begin with. And the Democrats themselves have acted in this way as well on several occasions (i.e. when it was to their advantage).

I find it absolutely wild that someone who never won a majority of the popular vote was actually formally elected. In other words he won legally, but not democratically, if democracy is taken to represent government by the rule of the majority. And now he and his cronies (and the extreme right in general, including and especially the Christian Right in this particular case) will use every lever they have to get a conservative/right wing majority on the US Supreme Court.

Anyways, just a long winded way of saying that I agree with you.

(What's depressing to me too is that Canada is veering to the right as well: the province of Ontario just elected Doug Ford, the brother of former Toronto mayor Rob Ford, who is really right wing.(1) My province of Quebec will soon decide between three right leaning parties and will probably choose the CAQ, which is really right wing.(2, 3) So the Justin Trudeau's liberals at the level of the federal government aren't completely bad, but a lot is decided at the provincial level in this country so...)

Add to that the right wingers being elected all over Europe (I was just disgusted with Italy's response to African migrants, recently), and it's just so incredibly depressing.